Rework compositor touch hit testing

Source/core/rendering/RenderBox.cpp

Index: Source/core/rendering/RenderBox.cpp
diff --git a/Source/core/rendering/RenderBox.cpp b/Source/core/rendering/RenderBox.cpp
index 30e8eb901e26a172d38dff8df9eab70e52d0d328..46e1dde1730661c91bfd3f0ba621fc5d2880ebd7 100644
--- a/Source/core/rendering/RenderBox.cpp
+++ b/Source/core/rendering/RenderBox.cpp
@@ -580,6 +580,18 @@ void RenderBox::addFocusRingRects(Vector<IntRect>& rects, const LayoutPoint& add
         rects.append(pixelSnappedIntRect(additionalOffset, size()));
 }
 
+void RenderBox::addLayerHitTestRects(LayerHitTestRects& layerRects, const RenderLayer* currentLayer, const LayoutPoint& layerOffset) const
+{
+    LayoutPoint adjustedLayerOffset = layerOffset + locationOffset();
+    RenderBoxModelObject::addLayerHitTestRects(layerRects, currentLayer, adjustedLayerOffset);
+}
+
+void RenderBox::computeOwnHitTestRects(Vector<IntRect>& rects, const LayoutPoint& layerOffset) const
+{
+    if (!size().isEmpty())
+        rects.append(pixelSnappedIntRect(layerOffset, size()));

[leviw_travelin_and_unemployed, 2013/07/18 18:08:39]

This won't actually get pixel snapping right since you're not using the
locationOffset. You should use enclosingIntRect (we don't mind if this is a
pixel too big, but we don't want a pixel too small).

[Rick Byers, 2013/07/18 19:58:52]

Done.  Also fixed RenderBlock::computeOwnHitTestRects.

On a related note, perhaps it would be simpler (and more precise) if I just
tracked LayoutRects here and converted to enclosing IntRect only just before
sending them to the compositor?

[leviw_travelin_and_unemployed, 2013/07/18 20:21:48]

Yes.

[Rick Byers, 2013/07/18 22:20:32]

Done.  The only complication was RenderInline::computeSelfHitTestRects - the
AbsoluteRectsGeneratorContext was designed just for IntRects (and none of the
other existing GeneratorContext objects seemed suitable), so I added a new one -
AbsoluteLayoutRectsGeneratorContext.

+}
+
 LayoutRect RenderBox::reflectionBox() const
 {
     LayoutRect result;